Exterior metal framing has always been difficult to insulate because of the configuration of the support channels like a C channel. The lip and flange of the C channel protrudes from the web making it difficult to insulate. When horizontal bracing channels are installed between support channels for additional strength, insulation became even more difficult to install as well as form a good insulated wall.
Closed cell rigid insulation has been increasing in popularity, however the solutions has been to mold the closed cell insulation into the support channels. In addition, closed cell rigid insulation has been cut into panels where several support channels slide into the rigid insulation panel from the top of the rigid insulation in order to install the support channels. The closed cell rigid insulation solutions are usually installed in a manufacturing plant rather that at the job site.
The creation of a smaller spacer blocks that has flexibility to be assembled into panels at a manufacturing plant or at the construction site as well as incorporating various types of horizontal bracing channels and electrical chases or troughs gives the spacer block additional flexibility. In addition, the size of the spacer block can vary depending on the type of closed cell rigid insulation is used like polystyrene, cellular light weight concrete or aerated autoclaved concrete.
The horizontal bracing channels within the wall forming structure is generally provided by installing bridging members which tie the support channels together. These bridging members may be attached on the outside of the flanges of the support channels or maybe internal bridging members installed through openings provided in the web of the support channels. None of the bridging members used today have a limited function and do not provide a solution for interacting with rigid insulation between support channels and the holes the internal bridging members pass through.
The construction of a wall varies based on the type of materials that are used. For example a solid concrete or masonry wall does not need to be laterally supported, because the wall is connected horizontally from say one masonry block to another masonry block. On the other hand, a post and beam type construction needs to be horizontally braced somewhere within that building otherwise the building would collapse if the wind or an earthquake would cause the building to move horizontally. Usually that is done by adding diagonal braces that criss-cross between the columns or by adding a solid wall somewhere within the building structure. When a smaller wood or metal framed wall has a similar problem, that is, the framing members need to be supported between each other using by applying plywood over the framing members. The plywood acts a shear wall, by not allowing the framing members to fall down like “domino's”.
Structural insulated panels or SIP's have a foam core with exterior skins usually plywood glued to the foam. Sometimes metal or wood is installed within the foam core and the wood or metal is connected between the panels for additional support. SIP's have a very limited load bearing capacity due to the structural limitation in the design of the panels. The use of SIP's have been limited to one or two story building and have never been used in conjunction with precast or poured-in-place concrete walls.